From 9032cd52798daf4cd6314ffea5030b37b3eb34af Mon Sep 17 00:00:00 2001 From: Sarah Sharp Date: Thu, 29 Jul 2010 22:12:29 -0700 Subject: USB: xhci: Performance - move interrupt handlers into xhci-ring.c Most of the work for interrupt handling is done in xhci-ring.c, so it makes sense to move the functions that are first called when an interrupt happens (xhci_irq() or xhci_msi_irq()) into xhci-ring.c, so that the compiler can better optimize them. Shorten some lines to make it pass checkpatch. Signed-off-by: Sarah Sharp Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci-ring.c | 103 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 103 insertions(+) (limited to 'drivers/usb/host/xhci-ring.c') diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index 7f1c545..4b50a02 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -2030,6 +2030,109 @@ void xhci_handle_event(struct xhci_hcd *xhci) /* Are there more items on the event ring? */ xhci_handle_event(xhci); } +/* + * Called in interrupt context when there might be work + * queued on the event ring + * + * xhci->lock must be held by caller. + */ +static void xhci_work(struct xhci_hcd *xhci) +{ + u32 temp; + u64 temp_64; + + /* + * Clear the op reg interrupt status first, + * so we can receive interrupts from other MSI-X interrupters. + * Write 1 to clear the interrupt status. + */ + temp = xhci_readl(xhci, &xhci->op_regs->status); + temp |= STS_EINT; + xhci_writel(xhci, temp, &xhci->op_regs->status); + /* FIXME when MSI-X is supported and there are multiple vectors */ + /* Clear the MSI-X event interrupt status */ + + /* Acknowledge the interrupt */ + temp = xhci_readl(xhci, &xhci->ir_set->irq_pending); + temp |= 0x3; + xhci_writel(xhci, temp, &xhci->ir_set->irq_pending); + + if (xhci->xhc_state & XHCI_STATE_DYING) + xhci_dbg(xhci, "xHCI dying, ignoring interrupt. " + "Shouldn't IRQs be disabled?\n"); + else + /* FIXME this should be a delayed service routine + * that clears the EHB. + */ + xhci_handle_event(xhci); + + /* Clear the event handler busy flag (RW1C); event ring is empty. */ + temp_64 = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue); + xhci_write_64(xhci, temp_64 | ERST_EHB, &xhci->ir_set->erst_dequeue); + /* Flush posted writes -- FIXME is this necessary? */ + xhci_readl(xhci, &xhci->ir_set->irq_pending); +} + +/* + * xHCI spec says we can get an interrupt, and if the HC has an error condition, + * we might get bad data out of the event ring. Section 4.10.2.7 has a list of + * indicators of an event TRB error, but we check the status *first* to be safe. + */ +irqreturn_t xhci_irq(struct usb_hcd *hcd) +{ + struct xhci_hcd *xhci = hcd_to_xhci(hcd); + u32 temp, temp2; + union xhci_trb *trb; + + spin_lock(&xhci->lock); + trb = xhci->event_ring->dequeue; + /* Check if the xHC generated the interrupt, or the irq is shared */ + temp = xhci_readl(xhci, &xhci->op_regs->status); + temp2 = xhci_readl(xhci, &xhci->ir_set->irq_pending); + if (temp == 0xffffffff && temp2 == 0xffffffff) + goto hw_died; + + if (!(temp & STS_EINT) && !ER_IRQ_PENDING(temp2)) { + spin_unlock(&xhci->lock); + xhci_warn(xhci, "Spurious interrupt.\n"); + return IRQ_NONE; + } + xhci_dbg(xhci, "op reg status = %08x\n", temp); + xhci_dbg(xhci, "ir set irq_pending = %08x\n", temp2); + xhci_dbg(xhci, "Event ring dequeue ptr:\n"); + xhci_dbg(xhci, "@%llx %08x %08x %08x %08x\n", + (unsigned long long) + xhci_trb_virt_to_dma(xhci->event_ring->deq_seg, trb), + lower_32_bits(trb->link.segment_ptr), + upper_32_bits(trb->link.segment_ptr), + (unsigned int) trb->link.intr_target, + (unsigned int) trb->link.control); + + if (temp & STS_FATAL) { + xhci_warn(xhci, "WARNING: Host System Error\n"); + xhci_halt(xhci); +hw_died: + xhci_to_hcd(xhci)->state = HC_STATE_HALT; + spin_unlock(&xhci->lock); + return -ESHUTDOWN; + } + + xhci_work(xhci); + spin_unlock(&xhci->lock); + + return IRQ_HANDLED; +} + +irqreturn_t xhci_msi_irq(int irq, struct usb_hcd *hcd) +{ + irqreturn_t ret; + + set_bit(HCD_FLAG_SAW_IRQ, &hcd->flags); + + ret = xhci_irq(hcd); + + return ret; +} /**** Endpoint Ring Operations ****/ -- cgit v1.1